Protecting means for markings in gas analysis apparatus



J. J. OLSEN' Oct. 17, 1950 PROTECTING MEANS FOR MARKINGS IN GAS ANALYSIS APPARATUS Filed May 24, 1948 INVENTOR.

JOHN J.OLSEN ATTOIIRNEYS Patented Oct. 17, 1950 PROTECTING MEANS FOR MARKINGS IN GAs ANALYSIS APPARATUS John J. Olsen, Chicago, 111., assignor, by mesne assignments, to Harry W. Dietert Company, Detroit, Mich., a corporation of Michigan Application May 24, 1948, Serial No. 28,929

2 Cl ms The invention relates to chemical apparatus including a calibrated tube or vessel which is surrounded by a transparent outer tube or vessel through which the calibrations must be viewed. More particularly, the invention relates to gas analyzing apparatus in which a burette having a calibrated portion is surrounded by an outer casing which at times contains a corrosive element such as potassium hydroxide .KOH. Such construction forms the subject matter of an application for patent by Harry W. Dietert, Serial No. 1,204, filed January 8, 1948.

It is the object of the invention to obtain a construction in which themarkings or calibrations are always plainly visible through the outer casing and are not ailected by its content. To this end the invention consists in the construction as hereinafter set forth. While my invention is applicable to chemical apparatus de signed for various purposes, I have specifically illustrated its application to a gas analyzing structure.

In the drawings:

Fig. 1 is a sectional elevation of the gas analyzing apparatus;

Fig. 2 is an enlarged sectional elevation showing a calibrated portion of the apparatus and the protecting means therefor; I

Fig. 3 is a cross-section on line 3-3, Fig. 2.

A designates in general a burette assembly which has a large diameter portion A and a depending small diameter calibrated portion A B is a transparent vessel surrounding the burette and spaced therefrom to form a con- 7 tainer for liquid; C is a vessel adjacent to the surrounding vessel B and Which as shown is pear-shaped having its lower end connected by a tube D with the portion B of the vessel B which surrounds the calibrated portion of the burette. The general construction of this gas analyzing apparatus forms no part of the instant invention, and I will therefore only briefly describe it as having a water bottle or displacement liquid holding casin E connected by a flexible tubing F to the lower end of the tube A There is also a tube G extending upward from the large diameter burette portion A and out from the vessel B to connect with a tube H containing a control valve I. This valve also controls an inlet tube J for the gas to be analyzed and an outlet tube K leading to the top of the vessel C. The arrangement is such that in one position of the valve I the inlet tube J communicates with the tube H and the burette, while in another position the tube H is connected with the tube K.

Thus, by raising or lowering the water bottle E, gas can be drawn into or expelled from the burette. By adjustment of the valve I the unan-.

alyzed gas is first drawn from the tube J intothe pburette in which its volume is measured by the liquid level in the calibrated tube portion A By then readjusting the valve I, the gas may be expelled from the. burette into the chamber C which contains an absorption liquid for one of the gas constituents, as for example CO2 carbon dioxide. The other constituents of the gas will expell the liquid from the vessel 0 forcing it through the tube D into the portion B and upward therein into the portion 13 of the burette assembly A. Finally the gas in the vessel C is returned to the buretteand its volume again measured by the calibrated portion A The difference between this volume and the one previously measured being the volume of gas absorbed.

The purpose of displacing the absorption liquid in the vessel C into a vessel surrounding the burette and then returning it again is to equalize the temperature of these two portions of the apparatus. This insures that the gas when returned into the burette will be at the same temperature as when it was first displaced therefrom, so that the volumetric measurement will correspond to weight measurement. However, as the absorption liquid KO'H highly corrosive, this might attack the markings on the calibrated portion of the burette and either obscure or obliterate the same. Such result I have prevented by the following construction.

As above stated thedepending tube A of the burette is the calibrated portion... These calibrations A and other markings are rendered visible by the use of a suitablepigment which, however, might be attacked'by the KOI-I or other absorption liquid. I therefore provide the calibrated portion A -with a surrounding transparent tube L which at its upper and lower ends is fused with or sealed to the tube A as indicated at M. This outer tube L covers the calibrations A and holds the liquid from contact therewith. At the same time the calibrations are clearly visible as both the tube L and the absorption liquid are transparent. Visibility is increased by placing on the rear side of the outer tube B a with said jacket and adapted to contain a corrosive gas absorption liquid medium, a second conduit connecting said burette to said vessel, a valve means located at the juncture of said second conduit and said vessel and extending substantially into said vessel, means for displacing gas from said burette through said second conduit to absorb a constitutent of the gas and to displace the liquid from said vessel into said jacket by an unabsorbed portion of the gas, and a, transparent tube surrounding the calibrated portion of said burette and sealed to the burette to prevent contact of the calibrated portion with the corrosive absorption liquid.

2. In a gas analyzing apparatus, a burette having a large diameter portion and a depending small diameter calibrated portion, a jacket surrounding both portions of said burette, a vessel at one side of said burette having conduit connection with said jacket and adapted to contain a corrosive gas absorption liquid medium, a second conduit connecting said burette to said vessel, a valve means located at the juncture of said second conduit and said vessel extending substantially into the liquid in said vessel, means for displacing gas from said burette through said second conduit into said vessel to absorb a constituent of the gas and to displace the liquid from said vessel into said jacket by an unabsorbed portion of the gas, and a transparent tube surrounding the calibrated portion of said burette and sealed to the burette to prevent contact of the calibrated portion With the corrosive absorption liquid.

JOHN J. OLSEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 717,654 Arndt Jan. 6, 1903 1,101,003 Zuckschwerdt June 23, 1914 1,719,864 Zimmerman July 9, 1929 2,009,943 Munsell et a1. July 30, 1935 2,163,000 Goodhue etal June 20, 1939 FOREIGN PATENTS Number Country Date 22,303 Great Britain Nov. 22, 1895 107,590 Germany Oct. 6, 1898 322,864 Germany Sept. 13, 1919 436,027 Germany Oct. 22, 1926 665,799 France Sept. 233, 1929 685,731

France Nov. 28, 1929 

1. IN A GAS ANALYZING APPARATUS, A BURETTE HAVING A CALIBRATED PORTION, A TRANSPARENT JACKET SURROUNDING SAID BURETTE, A VESSEL LOCATED AT ONE SIDE OF SAID BURETTE HAVING A CONDUIT CONNECTION WITH SAID JACKET AND ADAPTED TO CONTAIN A CORROSIVE GAS ABSORPTION LIQUID MEDIUM, A SECOND CONDUIT CONNECTING SAID BURETTE TO SAID VESSEL, A VALVE MEANS LOCATED AT THE JUNCTURE OF SAID SECOND CONDUIT AND SAID VESSEL AND EXTENDING SUBSTANTIALLY INTO SAID VESSEL, MEANS FOR DISPLACING GAS FROM SAID BURETTE THROUGH SAID SECOND CONDUIT TO ABSORB A CONSTITUTENT OF THE GAS AND TO DISPLACE THE LIQUID FROM SAID VESSEL INTO SAID JACKET BY AN UNABSORBED PORTION OF THE GAS, AND A TRANSPARENT TUBE SURROUNDING THE CALIBRATED PORTION OF SAID BURETTE AND SEALED TO THE BURETTE TO PREVENT CONTACT OF THE CALIBRATED PORTION WITH THE CORROSIVE ABSORPTION LIQUID. 